Interactive
CK-12 Foundation

Sums of Finite Arithmetic Series: Triangular Numbers

For Students 11th - Higher Ed
Using a slider, scholars build triangular numbers and their associated rectangles and use the geometric display to find the pattern to determine the next triangular number. They then relate that number to the area of the rectangle to...
Worksheet
Curated OER

Triangular Numbers

For Students Higher Ed
In this triangular numbers worksheet, students create a table of triangular numbers, write a formula for the nth number, and determine the sum of any two consecutive triangular numbers. This two-page worksheet contains five problems.
Assessment
Inside Mathematics

Rugs

For Teachers 8th Standards
The class braids irrational numbers, Pythagoras, and perimeter together. The mini-assessment requires scholars to use irrational numbers and the Pythagorean Theorem to find perimeters of rugs. The rugs are rectangular, triangular,...
Handout
Charleston School District

Volume of Composite Shapes

For Students 8th - 10th Standards
It's the parts that make the whole. Learners apply volume formulas to composite figures to find the total volume of the figure. Previous lessons in this series taught the methods for finding the volume and/or dimensions of...
Lesson Plan
EngageNY

Why Stay with Whole Numbers?

For Teachers 9th - 10th Standards
Domain can be a tricky topic, especially when you relate it to context, but here is a instructional activity that provides concrete examples of discrete situations and those that are continuous. It also addresses where the input values...
Lesson Plan
Curated OER

Triangular Numbers

For Teachers 3rd - 6th
Students are introduced to the problem and brainstorm ideas for approaching the problem and keeping track of what has been done. They work in pairs and share their answers, explaining their reasoning.
Lesson Plan
Curated OER

Square and Triangular Numbers

For Teachers 9th - 12th
Students use equations to represent practical situations. They solve linear equations and quadratic equations. The use of problem solving strategies is also developed.
Lesson Plan
Curated OER

Geometry In the Yard

For Teachers 5th - 7th
Students are responsible for creating a border around a triangular garden spot, of which they know the measurements for two sides. They use the Pythagorean Theorem to calculate the third side and complete the garden.
Lesson Plan
Curated OER

Navy Sail Design

For Teachers 9th - 12th
Students use the Pythagorean Theorem to explore sailboat design. In this Pythagorean Theorem lesson, two sides of a triangular sail are measured, and the theorem is used to calculate the third side. A worksheet, bulletin board design,...
Lesson Plan
Curated OER

Eigenvalues, Eigenvectors, and Diagonalization

For Teachers Higher Ed
Students determine eigenvectors and eigenvalues for a matrix. Students diagonalize a matrix. Similar matrices are defined. Determinant formula is given for an degree n polynomial.
Unit Plan
Bowland

Alien Invasion

For Teachers 6th - 9th
Win the war of the worlds! Scholars solve a variety of problems related to an alien invasion. They determine where spaceships have landed on a coordinate map, devise a plan to avoid the aliens, observe the aliens, and break a code to...
Lesson Plan
Pennsylvania Department of Education

A Geometric Scavenger Hunt

For Teachers 5th
Fifth graders connect their knowledge of polygons and polyhedrons. For this geometric shapes lesson, 5th graders identify and classify two- and three-dimensional objects. Students construct a polyhedron out of polygons and describe their...
Lesson Plan
Curated OER

Counting Pills

For Teachers 4th - 5th
Students are introduced to the problem. They brainstorm ideas for approaching the problem and keeping track of what has been done. Students work on the problem in pairs to discover what strategies might help to find the answer.
Lesson Plan
Curated OER

Double, Double: Looking at the Effect of Change on Perimeter, Area and Volume

For Teachers 9th - Higher Ed
Students explore perimeter, volume, and area. In this math instructional activity, students explore how changes in dimensions of geometric shapes affect the perimeter, area and volume of the various shapes. Students investigate the...
Worksheet
Curated OER

Numerical Analysis: Using the QR Algorithm

For Students Higher Ed
In this QR algorithm worksheet, students use the QR algorithm to solve an over-determined system of equations. This two-page worksheet contains 11 problems.
Worksheet
Curated OER

New York State Testing Program Grade 8 Math Sample Test 2005

For Students 8th
For this New York state sample test worksheet, 8th graders solve thirty-three sample math problems designed to help students prepare for the grade eight math test.  Tips for taking the test are provided.
Handout
Cut the Knot

Cut the Knot!: What Is a Number?

For Students 9th - 10th Standards
Casual and clear but definitely upper-level discussion of rational, real, imaginary, and several other types of numbers. Links to related sites.
Activity
Texas Instruments

Texas Instruments: Bats Triangular

For Teachers Pre-K - 1st
In this activity, students use manipulatives to construct a pyramid. The manipulative pyramid then becomes the basis students use to construct a pictorial representation of a pyramid. The TI-10 is used to show symbolic representation of...